Superb plugin!

The paid version is worth it! It’s much more than user-registration. You get User permissions, front-end Profile editor, front-end Registration, custom Fields, Photo and file uploads, public Profile pages, Admin Moderation of new users, a public Directory page of all users, and it’s really easy to use. The plugin is under active development, compatible with the most recent WordPress, and there’s a Free version. And the tech support is awesome!